In response shh!:
Total unexpected deaths from the western medical profession in USA was estimated as high as 800,000 per year (this would include all malpractice, iatrogenic disease, surgery and anesthesia problems, drug overdose, drug misuse and abuse and drug side-effects).
It is possible that part of the problem with researching something like this is that it often goes unreported. The lower estimates were specifically talking about reported incidents and may have been talking about only a certain category of drugs (non-steroidal anti-inflammatory drugs, for example). The upper end figures might be taking into account estimates from small groups that have been studied to try to catch deaths that would normally not be reported.
My research is that herbs are far, far safer on their worst day.
Now let us look at herbs. The very worst year for herbs came during the rampant abuse of Ma Huang by those trying to lose weight with it (this is not one of its clinical actions when used by responsible herbalists).
They were doing two really extreme things: first, they combined it with caffeine sources; second, they made standardised extracts that were standardised only to ephedrine (the strongest alkaloid) mixed in with questionable quality herbs (making something more like a drug than an herb).
Then this was taken in large doses by people who were desperate. I am not blaming them for being desperate, but I am saying this is an extremely unwise behavior. The results of that behavior with a drug would have been devastating (and were devastating if you remember the publicity about Fen-Phen).
What were the results of that abuse that year? An estimated 50 deaths. 50! That is about 1/1,000th, at best estimate, of the deaths due to drugs.
On average, herbs kill a grand total of 5-6 people per year and herbs get abused all the time. People use herbs in a crazy, out of balance way without even consulting a qualified herbalist and we still get 5-6 people per year.
There are a few more medical conditions blamed on herbs but believe me when I tell you that the most dangerous herb still in use is far safer than the safest over-the-counter drug.